This core is central for all transgenic and knockout experiments in this program project. Services that will be provided for by the core will include the generation of transgenic, knock-in and knockout animals, genotyping and transporting animals to Dr. Lederer for Project 3. The core will also provide support for the individual projects in the initial characterization of mouse models. The characterization of each mouse model will include careful analysis of the expression pattern of the transgene, and pathological and physiological changes, which occur as a result of transgene expression. In the past 5 years of the grant period the core managed over 300 cages of mice per year, assisted in pathological analysis of all new transgenic and knockout mice and performed physiological measurements on the mice. The core will provide support for the PPG in the following areas: A. The preparation and maintenance of genetic mouse models B. Characterization of transgenic, knock-in and knock-out mice including preparation and analysis of tissue specimens from animals C. Baseline physiological measurements including hemodynamics and echocardiography D. Physiological measurements on transgenic and knockout mice for drug testing. E. Non-invasive testing for VT in free ranging WT and transgenic mice F. Electrophysiological studies on the in vivo murine heart. G. Electrocardiogram and blood pressure recordings.